The present invention relates to a process for producing an anthracycline compound, R20X2 (13-deoxo-10-hydroxycarminomycin, hereinafter referred to as R20X2), which is useful as an antitumor antibiotic.
We have already found R20X2 in the culture broth of actinomycetes and applied for patents (Japanese Patent Laid-Open Pub. Nos. 33194/1986 and 76498/1986). In both patent applications, R20X2 was isolated from the culture broth of a microorganism. While methods based on the cultivation of microorganisms are per se useful, a more efficient method, if developed, would be advantageous as a matter of course.
One of the co-inventors of the present invention has also found in the culture broth of actinomycetes an anthracycline compound, R20X3 (13-deoxo-10-hydroxycarbonylcarminomyin, hereinafter referred to as R20X3), which can be a starting compound for the R20X2 of the present invention, and again applied for a patent (Japanese Patent Laid-Open Pub. No. 8300/1985).